From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED,USER_AGENT_NEOMUTT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id F2082C282CE for ; Mon, 15 Apr 2019 06:38:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C31CE20825 for ; Mon, 15 Apr 2019 06:38:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726216AbfDOGik (ORCPT ); Mon, 15 Apr 2019 02:38:40 -0400 Received: from orcrist.hmeau.com ([104.223.48.154]:59630 "EHLO deadmen.hmeau.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725796AbfDOGik (ORCPT ); Mon, 15 Apr 2019 02:38:40 -0400 Received: from gondobar.mordor.me.apana.org.au ([192.168.128.4] helo=gondobar) by deadmen.hmeau.com with esmtps (Exim 4.89 #2 (Debian)) id 1hFvGD-0003eS-MR; Mon, 15 Apr 2019 14:38:33 +0800 Received: from herbert by gondobar with local (Exim 4.89) (envelope-from ) id 1hFvGD-00044P-3B; Mon, 15 Apr 2019 14:38:33 +0800 Date: Mon, 15 Apr 2019 14:38:33 +0800 From: Herbert Xu To: Eric Biggers Cc: syzbot , davem@davemloft.net, linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, syzkaller-bugs@googlegroups.com, Ondrej Mosnacek Subject: Re: crypto: xts - Fix atomic sleep when walking skcipher Message-ID: <20190415063832.2qmhtek644nd2ywt@gondor.apana.org.au> References: <0000000000002bb2b105867bcd11@google.com> <20190414120338.edioq25dkafp2m7h@gondor.apana.org.au> <20190414163512.GA644@sol.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190414163512.GA644@sol.localdomain> User-Agent: NeoMutt/20170113 (1.7.2) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Apr 14, 2019 at 09:35:13AM -0700, Eric Biggers wrote: > > This isn't correct because skcipher_walk_virt() can still sleep when > atomic=true, since it may need to copy the IV. That's why I added might_sleep() > to it in commit bb648291fc04, and that's what's triggering here. Thanks for catching this Eric! > This is the correct fix: > > diff --git a/crypto/xts.c b/crypto/xts.c > index aed11e63ca315..359ef15e1673e 100644 > --- a/crypto/xts.c > +++ b/crypto/xts.c > @@ -101,6 +101,7 @@ static int xor_tweak(struct skcipher_request *req, bool second_pass) > req = &rctx->subreq; > /* set to our TFM to enforce correct alignment: */ > skcipher_request_set_tfm(req, tfm); > + req->base.flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP; > } This is what I'm doing in v2, except I've moved it over to crypt_done so that we don't affect the synchronous path. Cheers, -- Email: Herbert Xu Home Page: http://gondor.apana.org.au/~herbert/ PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt